Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit e4f82181 authored by Masami Hiramatsu's avatar Masami Hiramatsu Committed by Greg Kroah-Hartman
Browse files

ARM: 8771/1: kprobes: Prohibit kprobes on do_undefinstr 



commit eb0146daefdde65665b7f076fbff7b49dade95b9 upstream.

Prohibit kprobes on do_undefinstr because kprobes on
arm is implemented by undefined instruction. This means
if we probe do_undefinstr(), it can cause infinit
recursive exception.

Fixes: 24ba613c ("ARM kprobes: core code")
Signed-off-by: default avatarMasami Hiramatsu <mhiramat@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: default avatarRussell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 5f1d5f78

arch/arm/kernel/traps.c

+4 −1
Original line number Diff line number Diff line
@@ -19,6 +19,7 @@ 
#include <linux/uaccess.h>

#include <linux/hardirq.h>

#include <linux/kdebug.h>

#include <linux/kprobes.h>

#include <linux/module.h>

#include <linux/kexec.h>

#include <linux/bug.h>
@@ -395,7 +396,8 @@ void unregister_undef_hook(struct undef_hook *hook) 
	raw_spin_unlock_irqrestore(&undef_lock, flags);

}



static int call_undef_hook(struct pt_regs *regs, unsigned int instr)

static nokprobe_inline

int call_undef_hook(struct pt_regs *regs, unsigned int instr)

{

	struct undef_hook *hook;

	unsigned long flags;
@@ -468,6 +470,7 @@ die_sig: 


	arm_notify_die("Oops - undefined instruction", regs, &info, 0, 6);

}

NOKPROBE_SYMBOL(do_undefinstr)



/*

 * Handle FIQ similarly to NMI on x86 systems.